The effects of ionizing radiation on the thermophysical properties of substituted Sr-ferrites

Different samples of Sr-ferrites have been synthesized by the usual ceramic and high temperature sintering technique. On these samples, several measurements have been undertaken namely, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), the temperature dependence of DC electric conductivity before and after γ-absorbed dose, and the temperature dependence of dielectric constant. Results obtained were explained, correlated, interpreted and discussed in detail on the basis of the interaction of temperature, dopant cations and γ-radiation with the Sr-ferrite lattice. The activation energy (δE), energy gap for semi conduction and activation energy for γ-radiation-induced carrier liberation (χ) were evaluated for the first time. Finally, a mechanism for semi conductivity in terms of energy band picture in intrinsic ferrite semiconductors is suggested and discussed. (author). 13 refs., 5 figs